X-ray detectors are used in medical diagnostic imaging, medical therapy, and various medical testing and material analysis industries. A common type of x-ray detector uses scintillator materials to convert x-ray photons into visible-spectrum photons as part of the energy detection process, and solid state electronics to convert the visible light photons into digital signals. Scintillator materials can have an affinity to absorb moisture, and solid state electronics may corrode in the presence of moisture, both of which can adversely affect the structure of the scintillator and degrade the image quality of the image detector.
In one embodiment Dejule et al. (U.S. Pat. No. 7,473,903) describe a digital x-ray panel including an x-ray detector formed on a detector substrate, a dam formed on the detector substrate circumscribing the detector matrix, a scintillator material formed on the detector matrix, and a hermetic layer formed on the scintillator material extending on to the surface of the dam. The hermetic layer is deposited as a thin film or coating in an active detector area over the scintillator and detector matrix, encapsulating and hermetically sealing them therein. In other embodiments, additional hermetic seals are provided at a chest wall side of the digital x-ray panel comprising bonding adhesive sealant between an edge of the hermetic layer and a sidewall, and bonding adhesive sealant between an edge of the hermetic layer and an end channel. In another embodiment, an additional hermetic seal is provided comprising bonding adhesive sealant to seal a gap between a protective cover and the hermetic layer.
The inventors herein have recognized various issues with the above approach. Namely, forming a hermetic seal as a coating or thin film on the scintillator requires film deposition equipment which can increase manufacturing time and costs. Furthermore, because of its proximity to the active layers of the x-ray detector, forming the hermetic seal coating or thin film can damage the scintillator, detector matrix, or solid state electronics of the digital x-ray panel. Further still, forming a seal over the active detector area can interfere with the performance of the digital x-ray panel since incident x-rays must be transmitted through the seal prior to reaching the scintillator. Further still, providing multiple hermetic seals within an x-ray detector increases manufacturing complexity and costs. Further still, hermetic seals formed with thin film coatings and bonded adhesive sealant are not removable and resealable, rendering repair and refurbishing of the x-ray panel more difficult and costly.